Embodiments in accordance with principles of inventive concepts relate to a unit pixel of an image sensor and a pixel array including the unit pixel, and more particularly, to a unit pixel for increasing the resolution of an image sensor by having an area minimized.
Complementary metal oxide semiconductor (CMOS) image sensors are solid image pick-up, or capture, devices using CMOS. CMOS image sensors have lower manufacturing cost, smaller size and consume less power than charge-coupled device (CCD) image sensors, which require a high-voltage analog circuit. Furthermore, the performance of CMOS image sensors has continuously improved, and therefore, CMOS image sensors have found widespread use in electronic products, including portable devices such as smart phones and digital cameras.
A pixel array included in CMOS image sensors includes a photoelectric conversion element in each pixel. The photoelectric conversion element generates an electrical signal varying with the quantity of incident light. CMOS image sensors may process the electrical signal to synthesize an image. With the recent demand on high-resolution images, it is desired to miniaturize pixels in CMOS image sensors.